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CHMI 2227E Biochemistry I. Peptides General structure and properties. 1. 2. 1. 2. Peptides. A di peptide. Peptides. Peptides - polarity. Peptides - nomenclature. Peptide: hydrolysis. PITC = phenylisothiocyanate PTC = phenylthiocarbamyl. http://www.protein.iastate.edu/aaa.html.
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CHMI 2227EBiochemistry I Peptides General structure and properties CHMI 2227 - E.R. Gauthier, Ph.D.
1 2 1 2 Peptides A dipeptide CHMI 2227 - E.R. Gauthier, Ph.D.
Peptides CHMI 2227 - E.R. Gauthier, Ph.D.
Peptides - polarity CHMI 2227 - E.R. Gauthier, Ph.D.
Peptides - nomenclature CHMI 2227 - E.R. Gauthier, Ph.D.
Peptide: hydrolysis CHMI 2227 - E.R. Gauthier, Ph.D.
PITC = phenylisothiocyanate PTC = phenylthiocarbamyl http://www.protein.iastate.edu/aaa.html High Pressure Liquid Chromatography (HPLC) CHMI 2227 - E.R. Gauthier, Ph.D.
High Pressure Liquid Chromatography (HPLC) http://www.protein.iastate.edu/aaa_figure3.html CHMI 2227 - E.R. Gauthier, Ph.D.
Peptide - ionization CHMI 2227 - E.R. Gauthier, Ph.D.
COO- CH2 O H3N+-CH-C-NH-CH-C-OCH3 Asp-Phe-methyl ester CH2 O Disulfide bond S S Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2 Glycinamide residue: 2HN-CH2-CONH2 Example of peptides1. Aspartame: artificial sweetener 2. Oxytocin: stimulates uterine contractions CHMI 2227 - E.R. Gauthier, Ph.D.
Intrachain disulfide bond Interchain disulfide bonds Example of peptides3.Insulin CHMI 2227 - E.R. Gauthier, Ph.D.
Example of peptides4.Cystic Fibrosis Transductance Regulator CHMI 2227 - E.R. Gauthier, Ph.D.
General properties of proteins1. Proteins differ in their Mr. Source: Biochemistry. Lehninger. CHMI 2227 - E.R. Gauthier, Ph.D.
Monomer/subunit 1 2 1 1 Heterodimer Homodimer Hydrogen bonds: N-H ----- O-H N-H ----- N O-H ----- O=C N-H ----- O=C Electrostatic interactions: COO------ H3+N Hydrophobic interactions: -CH3 CH3- CH3 Multimeric proteins CHMI 2227 - E.R. Gauthier, Ph.D.
Importance of multimeric proteins – planar cell polarity CHMI 2227 - E.R. Gauthier, Ph.D.
Nature Genetics38, 21 - 23 (2006) Importance of multimeric proteins – planar cell polarity CHMI 2227 - E.R. Gauthier, Ph.D.
General properties of proteins2. Proteins differ in their pI. Source: Biochemistry. Lehninger. CHMI 2227 - E.R. Gauthier, Ph.D.
General properties of proteins3. Frequency of amino acid composition CHMI 2227 - E.R. Gauthier, Ph.D.
General properties of proteins3. Frequency of amino acid composition CHMI 2227 - E.R. Gauthier, Ph.D.
General properties of proteins4. Proteins can include other chemical groups in addition to amino acids CHMI 2227 - E.R. Gauthier, Ph.D.
Globular proteins Fibrillar (rod-like) proteins General properties of proteins5. Proteins have a specific shape CHMI 2227 - E.R. Gauthier, Ph.D.